NFS File close() appears not to await

[happybeing]

I have a scenario in SAFE Drive where I await on NFS File.close(), and it returns immediately (as if I had not used await). My code (not pushed) looks like this:

  async close (nfs) {
    try {
      this.releaseDescriptor()
      this._flags = undefined
      if (this._fileOpened) await this._fileOpened.close()
      return C.SUCCESS
    } catch (e) { error(e); return e }
    return new Error('Unknown error closing NFS file')
  }

If I break on the line: if (this._fileOpened) await this._fileOpened.close(), set a break on all the following lines in the function and 'run', I break immediately on the closing } of the function. What should happen is that I break at return C.SUCCESS.

This shows that the await on File.close() is not being honoured.

Repeating this in another scenario (reading the file I just created in the above process) the same thing is happening.

Looking at SAFE nodejs code it seems fine in api/emulations/nfs.js: https://github.com/maidsafe/safe_app_nodejs/blob/83a5bc47575270723c2fa748cde104d0ec770250/src/api/emulations/nfs.js#L194-L207

I don't understand the Rust code which is called by the above, so can't say if that might be the reason for this.

Steps to Reproduce (for bugs)

A bit involved, so first thing is for someone to inspect the Maidsafe code. I've looked as far as I can understand and it looks ok, so I suggest someone walk through using their eyes, including into the Rust to see if there is anything obvious before I explain how to do this with a SAFE Drive setup (which also needs me to commit stuff).

Your Environment

• Node version : 8.11.3
• Version or Branch used : SAFE Browser 0.11.2
• Operating System and version : Ubuntu 18.10
• Link to your project : https://github.com/theWebalyst/safe-drive